1. Field of the Invention
This invention is related to systems including integrated circuits and external memory accessible to the integrated circuits, and to dynamically changing operating points in such systems.
2. Description of the Related Art
As the number of transistors included on an integrated circuit “chip” continues to increase, power management in the integrated circuits continues to increase in importance. Power management can be critical to integrated circuits that are included in mobile devices such as personal digital assistants (PDAs), cell phones, smart phones, laptop computers, net top computers, etc. These mobile devices often rely on battery power, and reducing power consumption in the integrated circuits can increase the life of the battery. Additionally, reducing power consumption can reduce the heat generated by the integrated circuit, which can reduce cooling requirements in the device that includes the integrated circuit (whether or not it is relying on battery power).
One way to provide for power management is to support modes in an integrated circuit in which different clock frequencies, supply voltages, and other power management settings can be used based on the activity that is occurring in the integrated circuit. However, switching between modes can be very complex, and the complexity can increase with increased complexity of the integrated circuits. In many cases, switching between modes can involve resetting the integrated circuit to ensure that the integrated circuit can operate correctly at the new clock frequency.